FIG. 1 is a top perspective view of a reservoir plant stand showing our new design, with support feet therefor shown in broken lines for illustrative purposes only so that it forms no part of the claimed design;

FIG. 2 is a bottom perspective view of the reservoir plant stand shown in FIG. 1 with support feet therefor shown in broken lines for illustrative purposes only so that it forms no part of the claimed design;

FIG. 3 is a top plan view of the reservoir plant stand shown in FIGS. 1 and 2;

FIG. 4 is a bottom plan view of the reservoir plant stand shown in FIGS. 1 and 2 with support feet therefor shown in broken lines for illustrative purposes only so that it forms no part of the claimed design; and,

FIG. 5 is a side view in elevation of the reservoir plant stand shown in FIGS. 1 and 2 with support feet therefor shown in broken lines for illustrative purposes only so that it forms no part of the claimed design.